Railway traffic controlling system



Oct. 26, 1937. J. E. WILLING RAILWAY TRAFFIC CONTROLLING SYSTEM Filed001:. 26, 1935 ix {it IIYY'I' AAAAAAA ATTORNE'Y Patented Oct. 26, 1937UNITED STATES PATENT OFFICE Joseph E. Willing, Rochester, N. Y.,assignor to General Railway Signal Company, Rochester,

Application October 26, 1935, Serial No. 46,908

13 Claims.

This invention relates in general to traflic controlling systems forrailroads, and more particularly to means for indicating the position ofa railway trafiic controlling device.

In railway signalling systems, it is often necessary to conditioncertain apparatus at a remote location in accordance with the prevailingcondition of a traffic controlling device. A neutralpolar relay is oftenused for this purpose which is energized with one polarity or with theother polarity in accordance with the normal or reverse extreme positionof a track switch and which is deenergized when the switch is in anintermediate position. The clearing of signals over one route or overanother route may then be selected according to the position of thepolar contacts of the neutral-polar relay, and arranged so that neitherof these signals can be cleared unless the neutral contact is closed.However, in the event some abnormal condition prevents the polararmature of the usual type of neutral-polar relay from properlyresponding to a change in polarity of energization, the neutral armaturemay still be attracted, thereby clearing the signals over a wrong andpossibly an unsafe route.

In View of the above and other considerations, it is proposed inaccordance with the present invention to provide a means forconditioning a neutral-polar relay in accordance with the position of atraffic controlling device whereby the neutral armature can be attractedonly when the position of the polar armature corresponds to the polarityof energization of the relay. It is further proposed to provide such ameans for conditioning a neutral-polar relay which prevents attractionof the neutral armature in the event of a failure of any of theapparatus employed to check the proper polar contact operation, andwhich allows the neutral armature to be attracted only when the positionof the polar armature corresponds to the polarity of energizationregardless of the intensity of such energization.

Other objects, purposes and characteristic features of the presentinvention will be apparent as the description thereof progresses, duringwhich references will be made to the accompanying drawing which shows,in a diagrammatic and conventional manner, one specific embodiment ofthe present invention.

The accompanying drawing illustrates in a conventional manner a sectionof railway track including a track switch TS which is power operated bya switch machine SM of the type shown, for example, in Patent No.1,466,903, granted to a W. K. Howe, on September 4, 1923. A suitablepoint detector contact mechanism PD is associated with the switchmachine SM and track switch TS which may be of any suitable type such asshown in Patent No. 1,517,236, granted to C. S. Bushnell, on November25, 1924, which point detector mechanism has herein been shown mere 1yas two movable contacts I and 2 operable in unison to either of threepositions. It is believed to be suflicient for an understanding of thepresent invention to know that the contacts I and 2 are in their presentnormal position when the track switch TS is in its normal position inaccordance with the switch machine SM and is locked; that the contacts Iand 2 are in their center position whenever the track switch TS isunlocked or in operation; and that contacts I and 2 are in a reverse orlower extreme dotted position whenever the track switch TS is in itsreverse position in correspondence with the switch machine SM and islocked.

The contacts I and 2 of the point detector mechanism selectively controlthe energization of a line circuit including wires 3 and 4 from a localsource of energy such as a battery B, which line circuit is employed toenergize windings 5 and 6 of a neutral-polar relay generally constructedas shown for example in Patent No. 1,749,331 granted to O. S. Field, onMarch 4, 1930 with certain modifications as will be later pointed out.Such a relay has been illustrated in a simplified manner in the presentdrawing as comprising two parallel electro-magnet cores 9 and Iterminating at their lower ends in enlarged pole pieces and each joinedat their upper ends to the upper end of a center permanent magnet llextending parallel therewith. A polar armature I is mounted beneath thelower end of the permanent magnet l I so as to be magnetically coupledtherewith, and is operable about a pivot l6 into engagement with theinner vertical surface of the pole piece of either core 9 or II inaccordance with the polarity of energization of windings 5 and 6.

A suitable means is required to bias the polar armature IE to a centerposition midway between the two pole pieces of cores 9 and I0 when thepresent relay is deenergized, and in the present embodiment, this biasis provided by an opposed spring contact arrangement providing the usualmake-before-break contact operation. This contact arrangement is shownin a simplified manner as comprising a cross spring contact finger l8attached to an insulating member l9 which is in turn carried in asuitable manner by the lower 7 end of the polar armature'l5. The righthand ranged in a similar manner, or that is, a similar low resistancecontact point on this end is in its present position disengaged from acontact point of a stationary spring finger 22 which engages its 7 stopmember 23 to preventmovement thereof in the direction of the movablecontact finger l8.

It may now be seen that such a contact arrangement provides a biasingforce tending to center the polar armature 15,011 that is, with thepolar armature H3 in its illustrated-position,the

stationary spring finger 20 tends to operate the armature l 5 in aclock-wise direction but is overpowered by the magneticattraction ofarmature l 5 to its.illustratedposition. However, when the relaywindings are deenergized, the biasing force of .the stationary springfinger '20 is sufficient to operate. the armature A5 to the centerposition wherein the biasing force in'this direction'is stopped by itsengagement with the stop member 2i. The movable. finger l8 in thiscenter position engages the stationary finger 22 as well as thestationary finger 2Q, sothat a definite position of the polar armatureI5 is assured and the movablefinger 8 is electrically connected to boththe stationaryfingers 20'and 22. It will be obvious that the other orright hand position of the polar armature IS in a similar mannerdisengages the movable finger l8 from the stationary contact 20, butretains its engagement with contact 22, and upon deenergization of theoperation windings, the spring 22 acts to bias the armature l5 back toits center position in the same manner as spring finger 20. r

. A neutralv armature 25 is operable in the usual manner into engagementwith the lower surfaces of the pole pieces of cores 9 and I against agravity biased by the energization of Winding '5 a' polar contact 3! isalso shown conventionally with a dotted line indicating that it isoperated to either of three positions directly by the'polar armaturei5.- These neutral and polar contacts represented by contacts 30 and 3!may be em ployed to selectthe control or" various circuits such as theclearing of signals associated with routes over the track switch TS andfor the selectionof various locking and indicatingcircuits or the likein accordance with the usual practice.

Suitable asymmetric units or rectifiers and 8 are required in connectionwith'the present'neutral-polar relay, which may be of any suitable typeor the copper oxide type may be preferable as they may be convenientlymounted on the relay structure.

' Having thus described the apparatusemployed in the present invention,it is believed that the nature of the invention, its advantages andcharacteristic features can bestbe understood by further descriptionbeing given from the standpoint of operation.

Operation contact 2 in its upper position to the terminal of battery 13.It will be clear from the drawing that the potential of energy placed onwire 3 by the above circuit cannot cause current to flow, through'therectifier unit 1, and also that current cannot flow through winding 6due to open contacts l822. winding however produces a south magneticpole at the lower end of core 9, thus operating the upper endof polararmature 15 to the left into engagement with the side of the'pole pieceof core '9, this 'being due to the magnetism of armature i5 produced bythe north pole of permanent magnet The electro-magnetic flux produced bythe energization of winding '5 also attracts the neutral armature 25upwardly against the pole pieces of 'cores '9 and H3, Polar contact 3|and neutral contact 30 are thus operated to their illustrated positionsto complete a readily apparent circuit therethrough.

Now assuming that the track switch TS is operated to its reverseposition, the contacts I and 2 assume their center position during thisoperation thereby deen'e'rgizing the line wires 3 and 4 and shuntingthese wires over'a readily apparent circuit. The winding 5 isconsequently deenergized which releases the neutral armature 25 andallows the polar armature l5 to be operated by the spring finger 20 to acenter position, thereby opening neutral front contact 30 and When thetrack switch TS has completed its operation to its'reverse position, thecontacts 1 and 2 are operated to their lower dotted position whereby acircuit is completed from the terminal of battery B, through resistor R,point detector contact 2 in its lower dotted position, line wire 4,throughthe reverse operating windingfi, wire 35, contact 22-18, wire 35,rectifier unit 1, line wire 3, point detector contact I in its lowerdottedpositi'o'n "tothe side of battery 3. It will likewise be clearthat;th'is potential of energy on wire 4 cannot flow through therectifier unit 8, and as traced above, the majority of this currentrlowsthrough rectifier unit I rather than winding 5 in multipletherewith. The current flowing through winding 6, however, produces asouth magnetic pole at the lower end of core Ill, thereby attracting thepolar armature 15 to itsright hand position due to its magnetization bythe north pole of permanent magnet II. The electro-magnetic fluxproduced by this energization of winding "6 likewise attracts armature25,

' therebyclosing the neutral front contact 30. The

The current flowing in 7 operating polarconta'ct 3! to its center.position.

so that an unsafe condition cannot be produced by the picking up of theneutral armature 25 to close neutral front contact 30.

Also, considering that during the above operation of the track switchfrom its normal to its reverse position, some abnormal conditionprevented the movement of the polar armature l5 from its illustratedleft hand position upon deenergization of winding 5, it will be clearthat the winding 6 cannot be subsequently energized upon the completionof the operation of the track switch to its reverse position. In otherwords, if the polar armature I5 has not operated from its left handposition to its center position upon the operation of contacts I and 2to their reverse or lower positions, the potential of energy applied toline wire 4 cannot energize winding 6 as its circuit is open at contacts|8-22, and obviously rectifier unit 8 prevents the application of suchpotential over line wire 34 to winding 5, which winding 5 is alsoshunted to this polarity by rectifier unit I. In this manner, thewindings of the relay cannot be energized under the above assumedcondition to attract the neutral armature 25, thus retaining neutralfront contact 30 open to prevent the completion of an unsafe circuit dueto the improper position of polar contact 3!.

In a similar manner, it will be apparent that an unsafe circuit cannotbe completed during the reverse of the above assumed conditions, or thatis, when an abnormal condition prevents the polar armature fromoperating from its reverse or right hand position to its center positionduring the operation of the track switch from its reverse to its normalposition. In other words, with the armature l5 improperly retained inits reverse or right hand position, the application of potential to linewire 3 cannot energize winding 5 due to open contacts 20l8, and thispotential cannot energize winding 6 over wire 34 due to the rectifierunit 1, which winding 6 is further shunted to this polarity by rectifierunit 8.

It will be noticed in the above description of the manner in which animproper polar armature position prevents energization of the relay,that in each case the energization of one winding even though shunted bya rectifier unit was further prevented by the other rectifier unit.However, if either one or both of the rectifier units should becomeshort-circuited to pass current in either direction, they are soarranged that a shunt across line wires 3 and 4 would exist when apolarity of energization was applied thereto which was ordinarilyblocked by the defective rectifier.

Such a shunt across line wires 3 and 4 would obviously preventenergization of the relay to attract the neutral armature, therebypreventing an unsafe condition from obtaining due to a possible failureof a rectifier unit, and in order to prevent an unduly high current fromobtaining if such a shunt occurs across wires 3 and 4, the resistor Rhas been provided in series with battery B. It is of course obvioushowever, that the neutral armature can be attracted by one polarity ofenergization of the control circuit even though the rectifier employedto block the opposite polarity is short-circuited, providing that thepolar armature is not in an improper position, this being the normal andproper relay operation.

A means for conditioning a neutral-polar relay in accordance with theposition of a traffic controlling device has thus been provided, whereina biased-to-center polar armature is employed having a make-before-breakcontact arrangement in combination with rectifier units arranged toselect the energization of one or the other of two operating windingsaccording to the polarity of energization of the control circuit toaccordingly position the polar armature and attract the neutralarmature, and the polar armature thus properly positioned opens thecircuit for the coil which is not energized by the particular polarityof energization of the control circuit. Consequently if the polararmature sticks in an extreme operated position upon deenergization ofthe relay, the coil open circuited by the polar armature in thisposition cannot be subsequently energized and the rectifier arrangementprevents the other coil from being energized with a direction of currentwhich does not correspond to this extreme polar armature position, thuspreventing the neutral armature from being attracted by an energizationof the control line circuit which is out of correspondence with theposition of the polar armature.

An important feature of such an arrangement is the fact that the aboveoperation does not depend on any definite limits in the degree ofenergization of the relay, or that is, the neutral armature cannot beattracted when the polar armature is in an extreme position out ofcorrespondence with the polarity of energization even though thepotential of such energization is raised to an abnormally high value.Another important feature resides in the rectifier arrangement wherebythe neutral armature cannot be attracted in the event the rectifiersfail to block the opposed direction of current thereby preventing thepossibility of an improper and dangerous condition of the relay contactsfrom obtaining due to such a rectifier failure.

The above rather specific description of one form of the presentinvention is given solely by the way of example, and is not intended, inany manner whatsoever, in a limiting sense. It is also to be understoodthat various modifications, adaptations and alterations may be appliedto meet the requirement of practice, without in any manner departingfrom the spirit or scope of the present invention, except as limited bythe appended claims.

What I claim is:

1. In combination; a neutral-polar relay having a normal and a reverseoperating winding, a neutral armature, and a polar armature operable toa normal and a reverse position; means for biasing said polar armatureto a center position; oppositely arranged rectifiers; a normal contactclosed only by the center and the normal positions of the polararmature; a reverse contact closed only by the center and the reversepositions of the polar armature; an energizing circuit for attractingthe neutral armature and operating the polar armature to its normalposition including the normal operating winding, the normal contact, andone of the rectifiers; and an energizing circuit for attracting theneutral armature and operating the polar armature to the reverseposition including the reverse operating winding, the reverse contact,and the other of the rectifiers.

2. In combination; a neutral-polar relay having a polar armatureoperable to two energized positions; means for biasing said polararmature to a center position; contacts operated by the polar armature;two oppositely arranged rectifier units; a circuit for current flowingin one direction including one relay winding, a contact closed only bythe center and one operated position of rection including another relaywinding, a contact closed only by the center and the other operatedposition of the 'polar armature and the other of the rectifier units.

3. In combinationya neutral-polar relay havmeans for preventingenergization of either winding two operating windings and a polararmature operable to either a normal or a reverse position; means forbiasing said polar armature to a center position; contacts operated bythe polar armature; two oppositely arranged rectifier units; a circuitfor current fiowingin one direction including one of the relay windings,a contact closed only by the center and the normal position of the polararmature and one of the rectifier units; and a circuit for currentflowing in the other direction including another of the relay windings,a contact closed only by the center and the reverse position of thepolar armature and the other of the rectifier units.

4..In combination, a neutral-polar relay having a'three-position polararmature and a normal and a reverse operating winding, a rectifierpreventing the flow of current in one direction through the normaloperating winding, a rectifier preventing the fiow of current in theother direction through the reverse operating winding, polar contactmeans preventing the flow of current in either direction throughthereverse operating winding when the polar armature is in its normaloperated position, and polar contact means preventing the flow ofcurrent in either direction through the normal operating winding whenthe polar armature is in its reverse operatedposition. I V

5. In combination, a neutral-polar relay having'a three position polararmature, means permitting current ,to flow in one direction onlythrough one winding of the relay and in the other direction only throughanother winding of the relay, and contact means for preventingenergization of the one winding duringone operated position of the polararmature and the other windingduring the other operated position of thepolar armature. l

6. In combination, a neutral-polar relay having a three position polararmature, means permitting current to fiow in one direction only throughone winding of the relay and in the other direction only through anotherwinding of the relay, and contact means for preventing energization ofthe one winding during one operated position :of the polar armature andthe other winding during the other operated position of the polararmature whereby to prevent energization of the relay except by adirection of current corresponding to the operated position o-f-thepolar armature.

7 In combination, a neutral-polar relay having a three position polararmature, means permitting current to fiow in one direction only through,one winding of the relay and in the other direc- :tion only throughanother winding of -the relay,

contact means for preventing energization of theone winding during oneoperated position of the polar armature and the other winding during theother operated position of the-polar armature but permittingenergization of either'of the windings during a center position of thepolar armature,

ing with current of ing during an operated position of'the polararmature out of;correspondence therewith.

9. In combination, a polarized relay having a normal and a reversewinding on the same core and a neutral and a polar armature, rectifiermeans for shunting current of reverse polarity from said normal winding,means including said rectifier means for supplying said normalwindc-rinal polarity and said reverse winding with curre it of reversepolarity to operate said polar armature to 'its normal or reverseposition respectively, and means responsive to the operation of saidpolar armature to its normal or reverse position to open the circuit tosaid reverse winding or said normal winding respectiveiy.

10. In combination, a polarized relay having a normal and a reversewinding on the same core and a neutral and a polar armature, means forsupplying said normal winding with currentv of normal polarity and saidreverse winding with current of reverse polarity to operate said polararmature to its normal or reverse position respectively, meansresponsive to the operation of said polar armature to its normal orreverse position to open the circuit to said reverse winding or saidnormal winding respectively, means for shunting current of normalpolarity from said reverse winding and current of reverse polarity fromsaid normal winding, and a circuit having its continuity dependent onthe'cperation of said neutral and said polar armatures.

'11; In combination, an electro-magnetic relay comprising an armatureand two windings, a cir- 'cuit for said relaywindings, means forsupplying 12. In combination, an electro-magnetic relay comprising anarmature and a pair of windings, a circuit over which current or" normalor reverse polarity is supplied to said windings, a pair of oppositelypoled rectifiers connected across said circuit, and means controlled bysaid armature for selectively connecting said rectifiers to saidwindings. 7

13. In combination, an elcctro-magnetic relay comprising an armature anda of windings, a

circuit over which current of normal or reverse polarity is supplied tosaid windings, a pair of oppositely poled rectifiers'connectedacrosssaid circuit, means controlled by said armature for selectivelyconnecting said rectifie'rsto said windings, and means controlled bysaid windings and said rectifiers in-combination for selectivelycontrolling said armature. V

' JOSEPH E. WILLING.

